Do not allow dd-agent user to shell in
Remove dd-agent user and group on uninstall
Turn ssl validation of http_check into an option

Fixes #770.
Merge from master.
Revert source install `set -e`
#768 dd-agent is not part of any group on debian
Vagrant VM for development
Add a centos test box
Fix provisioning on redhat
Redhat package cleans up after itself
Make sure python is on debian7.1 to run the agent
TAB -> spaces in http_check.yaml example
Log a warning when graphite listener is on

Fixes #771
Use self.warning in lieu of self.log.warn
No home directory for dd-agent on RedHat
Set up a valid home directory even with no write access
Merge branch 'master' into pre-post-install-cleanup
A more robust ganglia test

@remh I have checked and we do not depend on the shell for the agent
proper. `test_ganglia.py` is run by travis or jenkins, while the
`boto.manage` stuff is a layer of server management built on top of
boto. Fixes #769.
Use the same home directory for centos 5 and centos 6
Merge pull request #778 from DataDog/pre-post-install-cleanup

Packaging clean-up + SSL warning in http_check